Term	Definition
Adhesive	The gum or coating on the back of a stamp which allows you to attach it to an envelope.
Album	A book for storing stamps. Most albums consist of pages pre-printed with stamp images, although a stockbook with pockets to hold stamps may also be considered an album.
Block	A group of attached stamps at least two wide and two tall.
Booklet Pane	A “page” of stamps from a booklet. Most panes consist of at least four stamps.
Cachet	A design or artwork on the left-hand side of an envelope, found primarily on first day covers.
Cancellation	A mark used by the post office to show that a stamp has been used.
Centring	The position of the design on a postage stamp. On perfectly centred stamps, the design is exactly in the middle (there is equal spacing on all four sides between the perforation and design).
Charity stamps	(aka “semi-postals”) Postage stamps which are used to raise funds for a charity. These stamps are sold for more than their postage value with the difference supporting a cause or charity.
Coils	Stamps sold in rolls. Two opposite edges (most often the top and bottom) usually have straight edges rather than perforations. Coils are issued for use in dispensers or vending machines or for automatic affixing equipment.
Commemoratives	A stamp issued for a limited period of time, usually at the first-class rate and in a larger format than most stamps. Commemoratives usually honour persons, organizations, events or causes on significant anniversaries.
Condition	Broadly this refers to what shape the stamp is in and will help in determining a stamp’s value. Condition considers questions such as: Is the stamp cancelled? Is it hinged? Does it have any flaws such as creases, thins, or short perforations? How well it is centred?
Cover	An envelope with a stamp or other means of postage payment.
Definitives	Used on most mail, generally these are smaller size stamps printed in huge quantities, often in a single colour ink, that are available from the post office for an indefinite period of time which may be many years.
Denomination	The amount of postage which the stamp pays.
Face Value	Another word for denomination.
First Day Cover	An envelope with a stamp cancelled on its first day of sale.
Gum	Adhesive that is used to attach a stamp to an envelope.
Hinges	Small pieces of gummed paper that are used to affix stamps to an album page. Hinges allow for stamps to be removed from an album page without damaging the stamp.
Imperforate	A stamp sold without perforations or separating holes.
Mint	A stamp in the same condition as originally issued. This means it has its full gum and has not been hinged.
Overprint	An additional printing on a stamp that was not part of the original design — such as additional words or symbols or even a new value. Typically overprints occur when there is not enough time to design and print a whole new stamp needed for some special reason or when rates increase. Precancels and surcharges are the most common types of overprints.
Pane	The proper name for a sheet of stamps sold at a post office. Most panes include a plate number and other markings in the margin or selvedge.
Perforations	Holes punched between stamps to make it easier for an individual to separate two or more stamps. Collectors use a perf gauge to measure the perforations helping them to identify their stamp.
Philately	The hobby of stamp collecting.
Plate Block	A block of four or more stamps that has a code (usually one or more numbers) printed on the margin (selvedge) identifying the printing plate used in the stamps’ production.
Postage Due	When a piece of mail is sent that does not have the proper amount of postage affixed, the post office will require the addressee to pay the additional postage due. Hence, a special type of stamp has been issued to collect unpaid postage.
Postal Stationery	An envelope, card, or aerogramme sold by the post office on which the image of a stamp is pre-printed. These stamps were printed as part of the stationery and thus cannot be soaked off.
Postmark	A mark indicating when and where a letter was handled, or giving postal information such as the route or postage due. It may or may not also serve as a cancellation.
Precancels	Stamps cancelled prior to the mailing of a letter. Sometimes referred to as Cancelled to Order (CTO). The idea is to eliminate the need to cancel the stamps; an effort to help to speed the handling of mail.
Revenue Stamps	Labels that do not pay postage but pay other fees or taxes.
Se-tenant	Two or more attached stamps with different designs.
Selvedge	(aka “selvage”) The margin of a pane of stamps that usually includes the plate number and other markings such as copyright notices.
Souvenir Sheet	Stamps issued in a special format primarily for stamp collectors. Most souvenir sheets include only one of each stamp design and usually have a special decorative border.
Special Stamps	Christmas, Love, and Greeting stamps that share some characteristics of definitives (larger printing quantities and may be reprinted) and some characteristics of commemoratives (often larger size and although they may be sold for longer periods than most commemoratives they are still sold for shorter periods of time than definitives).
Surcharge	A stamp that has been overprinted with a new denomination.
Thematics	A subject or topic of stamps such as those showing animals or trains, or a more general collection on a theme such as “Peace”. A collection of stamps and other philatelic items based on subject rather than country.
Tweezers	Tools with a smooth gripping service used to handle stamps.
Watermark	A special mark incorporated into postage stamp paper as a security device, making it more difficult to counterfeit a stamp. Watermarks are thinner parts of the paper that sometimes may be seen by looking at the back of a stamp but often require dipping in special fluid to be visible.